Acts as go-between (8)
I believe the answer is:
mediates
'acts as go-between' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for mediates that I've seen before include "Acts as go-between or peacemaker" , "Liaises" , "Intercedes or arbitrates" , "restores harmony" , "Referees" .)